Add 70/21 and 9/40
1st number: 3 7/21, 2nd number: 9/40
70/21 + 9/40 is 427/120.
Steps for adding fractions
- Find the least common denominator or LCM of the two denominators:
LCM of 21 and 40 is 840
Next, find the equivalent fraction of both fractional numbers with denominator 840 - For the 1st fraction, since 21 × 40 = 840,
70/21 = 70 × 40/21 × 40 = 2800/840 - Likewise, for the 2nd fraction, since 40 × 21 = 840,
9/40 = 9 × 21/40 × 21 = 189/840 - Add the two like fractions:
2800/840 + 189/840 = 2800 + 189/840 = 2989/840 - 2989/840 simplified gives 427/120
- So, 70/21 + 9/40 = 427/120
In mixed form: 367/120
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